Differential expression of extracellular thiol groups of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on S0 and Fe2+
Differential expression of extracellular thiol groups of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on S0 and Fe2+
复制标题
DOI：
10.1007/s00203-015-1111-6
复制
发表时间：
2015-08-01
影响因子：
2.8
通讯作者：
Zhang, Li-juan
中科院分区：
文献类型：
--
作者：
Liu, Hong-chang;Xia, Jin-lan;Zhang, Li-juan
单质硫的生物氧化在生物浸出和硫循环中具有重要意义。提出S-0首先通过与外膜蛋白的反应性巯基（-SH）反应而被活化，形成-S（n）H（n a parts per thousand yen 2）复合物。利用同步辐射扫描透射X射线显微镜（STXM）成像和微束X射线荧光（mu-XRF）图谱分析了中等嗜热氧化热硫化杆菌（Sulfobacillusthermersulfidooxidans）和极端嗜热曼扎嗜酸菌（Acidianusmanzaensis）在Fe 2+和S-0上的-SH差异表达。细胞外-SH的STXM成像和mu-XRF绘图基于结合在细胞上的Ca 2+的分析。通过比较Ca ~（2+）标记前后细胞内Ca ~（2+）的变化，得到巯基的分布和含量。结果表明，S. thermosulfidooxidans和A. S-0培养的细胞外-SH表达高于Fe ~（2+）培养的细胞。统计分析表明，S. thermosulfidooxidans和A.在S-0上生长的Manzaensis分别是在Fe ~（2+）上生长的2.37倍和2.14倍。这些结果表明，细胞外的硫醇基团最有可能参与元素硫的活化和嗜酸硫氧化微生物的氧化。
Bio-oxidation of elemental sulfur (S-0) is very important in bioleaching and sulfur cycle. S-0 was proposed to be first activated by reacting with reactive thiol groups (-SH) of outer membrane proteins, forming -S (n) H (n a parts per thousand yen 2) complexes. The differential expression of -SH of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on Fe2+ and S-0 was investigated by synchrotron radiation-based scanning transmission X-ray microscopy (STXM) imaging and micro-beam X-ray fluorescence (mu-XRF) mapping. The STXM imaging and mu-XRF mapping of extracellular -SH were based on the analysis of Ca2+ bound on the cell. By comparing Ca2+ of the cells with and without labeling by Ca2+, the distribution and content of thiol groups were obtained. The results showed that, for both S. thermosulfidooxidans and A. manzaensis, the expression of extracellular -SH of S-0-grown cells was higher than that of Fe2+-grown cells. Statistical analysis indicated that the expression of extracellular -SH for S. thermosulfidooxidans and A. manzaensis grown on S-0 was 2.37 times and 2.14 times, respectively, to that on Fe2+. These results evidently demonstrate that the extracellular thiol groups are most probably involved in elemental sulfur activation and oxidation of the acidophilic sulfur-oxidizing microorganisms.